relay.h File Reference

Header file for relay.c. More...

#include "core/or/relay_msg_st.h"

Go to the source code of this file.

Macros
#define	CONTROL_CELL_ID   0
#define	relay_send_command_from_edge(stream_id, circ, relay_command, payload, payload_len, cpath_layer)
#define	packed_cell_free(cell)    FREE_AND_NULL(packed_cell_t, packed_cell_free_, (cell))
#define	update_circuit_on_cmux(circ, direction)    update_circuit_on_cmux_((circ), (direction), SHORT_FILE__, __LINE__)

Functions
const char *	relay_command_to_string (uint8_t command)
void	relay_consensus_has_changed (const networkstatus_t *ns)
uint32_t	relay_get_param_max_circuit_cell_queue_size (const networkstatus_t *ns)
int	circuit_receive_relay_cell (cell_t *cell, circuit_t *circ, cell_direction_t cell_direction)
size_t	cell_queues_get_total_allocation (void)
int	relay_send_command_from_edge_ (streamid_t stream_id, circuit_t *circ, uint8_t relay_command, const char *payload, size_t payload_len, crypt_path_t *cpath_layer, const char *filename, int lineno)
int	connection_edge_send_command (edge_connection_t *fromconn, uint8_t relay_command, const char *payload, size_t payload_len)
int	connection_edge_package_raw_inbuf (edge_connection_t *conn, int package_partial, int *max_cells)
void	connection_edge_consider_sending_sendme (edge_connection_t *conn)
void	circuit_reset_sendme_randomness (circuit_t *circ)
void	dump_cell_pool_usage (int severity)
size_t	packed_cell_mem_cost (void)
int	have_been_under_memory_pressure (void)
void	packed_cell_free_ (packed_cell_t *cell)
void	cell_queue_init (cell_queue_t *queue)
void	cell_queue_clear (cell_queue_t *queue)
void	cell_queue_append (cell_queue_t *queue, packed_cell_t *cell)
void	cell_queue_append_packed_copy (circuit_t *circ, cell_queue_t *queue, int exitward, const cell_t *cell, int wide_circ_ids, int use_stats)
int	append_cell_to_circuit_queue (circuit_t *circ, channel_t *chan, cell_t *cell, cell_direction_t direction, streamid_t fromstream)
void	destroy_cell_queue_init (destroy_cell_queue_t *queue)
void	destroy_cell_queue_clear (destroy_cell_queue_t *queue)
void	destroy_cell_queue_append (destroy_cell_queue_t *queue, circid_t circid, uint8_t reason)
void	channel_unlink_all_circuits (channel_t *chan, smartlist_t *detached_out)
int	channel_flush_from_first_active_circuit (channel_t *chan, int max)
int	circuit_package_relay_cell (cell_t *cell, circuit_t *circ, cell_direction_t cell_direction, crypt_path_t *layer_hint, streamid_t on_stream, const char *filename, int lineno)
void	update_circuit_on_cmux_ (circuit_t *circ, cell_direction_t direction, const char *file, int lineno)
int	append_address_to_payload (uint8_t *payload_out, const tor_addr_t *addr)
const uint8_t *	decode_address_from_payload (tor_addr_t *addr_out, const uint8_t *payload, int payload_len)
void	circuit_clear_cell_queue (circuit_t *circ, channel_t *chan)
circid_t	packed_cell_get_circid (const packed_cell_t *cell, int wide_circ_ids)
uint8_t	packed_cell_get_command (const packed_cell_t *cell, int wide_circ_ids)
relay_cell_fmt_t	circuit_get_relay_format (const circuit_t *circ, const crypt_path_t *cpath)
size_t	circuit_max_relay_payload (const circuit_t *circ, const crypt_path_t *cpath, uint8_t relay_command)

Variables
uint64_t	stats_n_relay_cells_relayed
uint64_t	stats_n_relay_cells_delivered
uint64_t	stats_n_circ_max_cell_reached
uint64_t	stats_n_circ_max_cell_outq_reached
uint64_t	stats_n_data_cells_packaged
uint64_t	stats_n_data_bytes_packaged
uint64_t	stats_n_data_cells_received
uint64_t	stats_n_data_bytes_received
uint64_t	oom_stats_n_bytes_removed_dns
uint64_t	oom_stats_n_bytes_removed_cell
uint64_t	oom_stats_n_bytes_removed_geoip
uint64_t	oom_stats_n_bytes_removed_hsdir

Detailed Description

Header file for relay.c.

Header file for relay_crypto_tor1.c.

Definition in file relay.h.

Macro Definition Documentation

CONTROL_CELL_ID

#define CONTROL_CELL_ID   0

Definition at line 42 of file relay.h.

packed_cell_free

#define packed_cell_free

(

cell

)

FREE_AND_NULL(packed_cell_t, packed_cell_free_, (cell))

Definition at line 74 of file relay.h.

relay_send_command_from_edge

#define relay_send_command_from_edge	(		stream_id,
			circ,
			relay_command,
			payload,
			payload_len,
			cpath_layer
	)

Value:

  relay_send_command_from_edge_((stream_id), (circ), (relay_command),   \
                                (payload), (payload_len), (cpath_layer), \
                                __FILE__, __LINE__)

Definition at line 43 of file relay.h.

update_circuit_on_cmux

#define update_circuit_on_cmux	(		circ,
			direction
	)		update_circuit_on_cmux_((circ), (direction), SHORT_FILE__, __LINE__)

Definition at line 104 of file relay.h.

Function Documentation

append_address_to_payload()

int append_address_to_payload	(	uint8_t *	payload_out,
		const tor_addr_t *	addr
	)

Append an encoded value of addr to payload_out, which must have at least 18 bytes of free space. The encoding is, as specified in tor-spec.txt: RESOLVED_TYPE_IPV4 or RESOLVED_TYPE_IPV6 [1 byte] LENGTH [1 byte] ADDRESS [length bytes] Return the number of bytes added, or -1 on error

Definition at line 3443 of file relay.c.

append_cell_to_circuit_queue()

int append_cell_to_circuit_queue	(	circuit_t *	circ,
		channel_t *	chan,
		cell_t *	cell,
		cell_direction_t	direction,
		streamid_t	fromstream
	)

Add cell to the queue of circ writing to chan transmitting in direction.

The given cell is copied onto the circuit queue so the caller must cleanup the memory.

This function is part of the fast path.

Return 1 if the cell was successfully sent. Return 0 if the cell can not be sent. The caller MUST NOT close the circuit. Return -1 indicating an error and that the caller should mark the circuit for close.

Definition at line 3352 of file relay.c.

Referenced by circuit_deliver_create_cell(), circuit_package_relay_cell(), circuit_receive_relay_cell(), and onionskin_answer().

cell_queue_append()

void cell_queue_append	(	cell_queue_t *	queue,
		packed_cell_t *	cell
	)

Append cell to the end of queue.

Definition at line 2702 of file relay.c.

Referenced by cell_queue_append_packed_copy().

cell_queue_append_packed_copy()

void cell_queue_append_packed_copy	(	circuit_t *	circ,
		cell_queue_t *	queue,
		int	exitward,
		const cell_t *	cell,
		int	wide_circ_ids,
		int	use_stats
	)

Append a newly allocated copy of cell to the end of the exitward (or app-ward) queue of circ. If use_stats is true, record statistics about the cell.

Definition at line 2713 of file relay.c.

Referenced by append_cell_to_circuit_queue().

cell_queue_clear()

void cell_queue_clear

(

cell_queue_t *

queue

)

Remove and free every cell in queue.

Definition at line 2737 of file relay.c.

Referenced by circuit_clear_cell_queue(), circuit_free_(), and marked_circuit_free_cells().

cell_queue_init()

void cell_queue_init

(

cell_queue_t *

queue

)

Initialize queue as an empty cell queue.

Definition at line 2729 of file relay.c.

Referenced by init_circuit_base(), and or_circuit_new().

cell_queues_get_total_allocation()

size_t cell_queues_get_total_allocation

(

void

)

Definition at line 2837 of file relay.c.

channel_flush_from_first_active_circuit()

int channel_flush_from_first_active_circuit	(	channel_t *	chan,
		int	max
	)

Pull as many cells as possible (but no more than max) from the queue of the first active circuit on chan, and write them to chan->outbuf. Return the number of cells written. Advance the active circuit pointer to the next active circuit in the ring.

Definition at line 3092 of file relay.c.

Referenced by channel_flush_some_cells().

channel_unlink_all_circuits()

void channel_unlink_all_circuits	(	channel_t *	chan,
		smartlist_t *	circuits_out
	)

Remove all circuits from the cmux on chan.

If circuits_out is non-NULL, add all detached circuits to circuits_out.

Definition at line 2984 of file relay.c.

Referenced by circuit_unlink_all_from_channel().

circuit_clear_cell_queue()

void circuit_clear_cell_queue	(	circuit_t *	circ,
		channel_t *	chan
	)

Remove all the cells queued on circ for chan.

Definition at line 3497 of file relay.c.

Referenced by circuit_about_to_free(), circuit_about_to_free_atexit(), and handle_relay_msg().

circuit_get_relay_format()

relay_cell_fmt_t circuit_get_relay_format	(	const circuit_t *	circ,
		const crypt_path_t *	cpath
	)

Return the format to use.

NULL can be passed but not for both.

Definition at line 3537 of file relay.c.

Referenced by circuit_max_relay_payload(), circuit_receive_relay_cell(), connection_edge_get_inbuf_bytes_to_package(), and relay_send_command_from_edge_().

circuit_max_relay_payload()

size_t circuit_max_relay_payload	(	const circuit_t *	circ,
		const crypt_path_t *	cpath,
		uint8_t	relay_command
	)

Return the maximum relay payload that can be sent to the chosen point, with the specified command.

Definition at line 3555 of file relay.c.

Referenced by circuit_send_intermediate_onion_skin(), command_process_created_cell(), and connection_ap_handshake_send_begin().

circuit_package_relay_cell()

int circuit_package_relay_cell	(	cell_t *	cell,
		circuit_t *	circ,
		cell_direction_t	cell_direction,
		crypt_path_t *	layer_hint,
		streamid_t	on_stream,
		const char *	filename,
		int	lineno
	)

Package a relay cell from an edge:

• Encrypt it to the right layer
• Append it to the appropriate cell_queue on circ.

Return 1 if the cell was successfully sent as in queued on the circuit. Return 0 if the cell needs to be dropped as in ignored. Return -1 on error for which the circuit should be marked for close.

Definition at line 390 of file relay.c.

Referenced by relay_send_command_from_edge_().

circuit_receive_relay_cell()

int circuit_receive_relay_cell	(	cell_t *	cell,
		circuit_t *	circ,
		cell_direction_t	cell_direction
	)

Receive a relay cell:

• Crypt it (encrypt if headed toward the origin or if we are the origin; decrypt if we're headed toward the exit).
• Check if recognized (if exitward).
• If recognized and the digest checks out, then find if there's a stream that the cell is intended for, and deliver it to the right connection_edge.
• If not recognized, then we need to relay it: append it to the appropriate cell_queue on circ.

Return -reason on failure, else 0.

Definition at line 236 of file relay.c.

Referenced by circuit_receive_relay_cell(), and command_process_relay_cell().

circuit_reset_sendme_randomness()

void circuit_reset_sendme_randomness

(

circuit_t *

circ

)

Called when initializing a circuit, or when we have reached the end of the window in which we need to send some randomness so that incoming sendme cells will be unpredictable. Resets the flags and picks a new window.

Definition at line 2193 of file relay.c.

Referenced by connection_edge_get_inbuf_bytes_to_package(), and init_circuit_base().

connection_edge_package_raw_inbuf()

int connection_edge_package_raw_inbuf	(	edge_connection_t *	conn,
		int	package_partial,
		int *	max_cells
	)

If conn has an entire relay payload of bytes on its inbuf (or package_partial is true), and the appropriate package windows aren't empty, grab a cell and send it down the circuit.

If *max_cells is given, package no more than max_cells. Decrement *max_cells by the number of cells packaged.

Return -1 (and send a RELAY_COMMAND_END cell if necessary) if conn should be marked for close, else return 0.

Definition at line 2277 of file relay.c.

Referenced by circuit_resume_edge_reading_helper(), connection_ap_handshake_send_begin(), connection_edge_process_inbuf(), connection_edge_process_relay_cell_not_open(), and process_sendme_cell().

connection_edge_send_command()

int connection_edge_send_command	(	edge_connection_t *	fromconn,
		uint8_t	relay_command,
		const char *	payload,
		size_t	payload_len
	)

Make a relay cell out of relay_command and payload, and send it onto the open circuit circ. fromconn is the stream that's sending the relay cell, or NULL if it's a control cell. cpath_layer is NULL for OR->OP cells, or the destination hop for OP->OR cells.

If you can't send the cell, mark the circuit for close and return -1. Else return 0.

Definition at line 762 of file relay.c.

Referenced by circuit_send_stream_xoff(), circuit_send_stream_xon(), connection_ap_handshake_send_begin(), connection_ap_handshake_send_resolve(), connection_edge_end(), connection_edge_finished_connecting(), connection_edge_package_raw_inbuf(), connection_exit_connect(), connection_exit_connect_dir(), send_resolved_cell(), send_resolved_hostname_cell(), and sendme_connection_edge_consider_sending().

decode_address_from_payload()

const uint8_t * decode_address_from_payload	(	tor_addr_t *	addr_out,
		const uint8_t *	payload,
		int	payload_len
	)

Given payload_len bytes at payload, starting with an address encoded as by append_address_to_payload(), try to decode the address into *addr_out. Return the next byte in the payload after the address on success, or NULL on failure.

Definition at line 3469 of file relay.c.

destroy_cell_queue_append()

void destroy_cell_queue_append	(	destroy_cell_queue_t *	queue,
		circid_t	circid,
		uint8_t	reason
	)

Append a destroy cell for circid to queue.

Definition at line 2797 of file relay.c.

destroy_cell_queue_clear()

void destroy_cell_queue_clear

(

destroy_cell_queue_t *

queue

)

Remove and free every cell in queue.

Definition at line 2771 of file relay.c.

Referenced by circuitmux_free_().

destroy_cell_queue_init()

void destroy_cell_queue_init

(

destroy_cell_queue_t *

queue

)

Initialize queue as an empty cell queue.

Definition at line 2763 of file relay.c.

Referenced by circuitmux_alloc().

dump_cell_pool_usage()

void dump_cell_pool_usage

(

int

severity

)

Log current statistics for cell pool allocation at log level severity.

Definition at line 2675 of file relay.c.

Referenced by dumpmemusage().

have_been_under_memory_pressure()

int have_been_under_memory_pressure

(

void

)

Return true if we've been under memory pressure in the last MEMORY_PRESSURE_INTERVAL seconds.

Definition at line 2928 of file relay.c.

packed_cell_free_()

void packed_cell_free_

(

packed_cell_t *

cell

)

Return a packed cell used outside by channel_t lower layer

Definition at line 2665 of file relay.c.

packed_cell_get_circid()

circid_t packed_cell_get_circid	(	const packed_cell_t *	cell,
		int	wide_circ_ids
	)

Extract the circuit ID from a packed cell.

Definition at line 3078 of file relay.c.

packed_cell_get_command()

uint8_t packed_cell_get_command	(	const packed_cell_t *	cell,
		int	wide_circ_ids
	)

Extract the command from a packed cell.

Definition at line 3067 of file relay.c.

Referenced by channel_flush_from_first_active_circuit(), and write_packed_cell().

packed_cell_mem_cost()

size_t packed_cell_mem_cost

(

void

)

Return the total number of bytes used for each packed_cell in a queue. Approximate.

Definition at line 2830 of file relay.c.

Referenced by circuits_handle_oom().

relay_command_to_string()

const char * relay_command_to_string

(

uint8_t

command

)

Convert the relay command into a human-readable string.

Definition at line 526 of file relay.c.

Referenced by fill_single_stream_value(), and relay_send_command_from_edge_().

relay_consensus_has_changed()

void relay_consensus_has_changed

(

const networkstatus_t *

ns

)

Definition at line 3328 of file relay.c.

relay_send_command_from_edge_()

int relay_send_command_from_edge_	(	streamid_t	stream_id,
		circuit_t *	orig_circ,
		uint8_t	relay_command,
		const char *	payload,
		size_t	payload_len,
		crypt_path_t *	cpath_layer,
		const char *	filename,
		int	lineno
	)

Make a relay cell out of relay_command and payload, and send it onto the open circuit circ. stream_id is the ID on circ for the stream that's sending the relay cell, or 0 if it's a control cell. cpath_layer is NULL for OR->OP cells, or the destination hop for OP->OR cells.

If you can't send the cell, mark the circuit for close and return -1. Else return 0.

Definition at line 581 of file relay.c.

update_circuit_on_cmux_()

void update_circuit_on_cmux_	(	circuit_t *	circ,
		cell_direction_t	direction,
		const char *	file,
		int	lineno
	)

Update the number of cells available on the circuit's n_chan or p_chan's circuit mux.

Definition at line 2939 of file relay.c.

Variable Documentation

oom_stats_n_bytes_removed_cell

uint64_t oom_stats_n_bytes_removed_cell

extern

Definition at line 2850 of file relay.c.

oom_stats_n_bytes_removed_dns

uint64_t oom_stats_n_bytes_removed_dns

extern

Statistics on how many bytes were removed by the OOM per type.

Definition at line 2849 of file relay.c.

Referenced by cell_queues_check_size(), and fill_oom_values().

oom_stats_n_bytes_removed_geoip

uint64_t oom_stats_n_bytes_removed_geoip

extern

Definition at line 2851 of file relay.c.

oom_stats_n_bytes_removed_hsdir

uint64_t oom_stats_n_bytes_removed_hsdir

extern

Definition at line 2852 of file relay.c.

stats_n_circ_max_cell_outq_reached

uint64_t stats_n_circ_max_cell_outq_reached

extern

Definition at line 145 of file relay.c.

stats_n_circ_max_cell_reached

uint64_t stats_n_circ_max_cell_reached

extern

Stats: how many circuits have we closed due to the cell queue limit being reached (see append_cell_to_circuit_queue())

Definition at line 144 of file relay.c.

Referenced by append_cell_to_circuit_queue(), and fill_dos_values().

stats_n_data_bytes_packaged

uint64_t stats_n_data_bytes_packaged

extern

How many bytes of data have we put in relay_data cells have we built, ever? This would be RELAY_PAYLOAD_SIZE*stats_n_data_cells_packaged if every relay cell we ever sent were completely full of data.

Definition at line 2179 of file relay.c.

Referenced by connection_edge_package_raw_inbuf(), dumpstats(), and log_heartbeat().

stats_n_data_bytes_received

uint64_t stats_n_data_bytes_received

extern

How many bytes of data have we received relay_data cells, ever? This would be RELAY_PAYLOAD_SIZE*stats_n_data_cells_packaged if every relay cell we ever received were completely full of data.

Definition at line 2185 of file relay.c.

Referenced by dumpstats(), and handle_relay_msg().

stats_n_data_cells_packaged

uint64_t stats_n_data_cells_packaged

extern

How many relay_data cells have we built, ever?

Definition at line 2175 of file relay.c.

Referenced by connection_edge_package_raw_inbuf(), dumpstats(), and log_heartbeat().

stats_n_data_cells_received

uint64_t stats_n_data_cells_received

extern

How many relay_data cells have we received, ever?

Definition at line 2181 of file relay.c.

Referenced by dumpstats(), and handle_relay_msg().

stats_n_relay_cells_delivered

uint64_t stats_n_relay_cells_delivered

extern

Stats: how many relay cells have been delivered to streams at this hop?

Definition at line 141 of file relay.c.

Referenced by circuit_receive_relay_cell(), and dumpstats().

stats_n_relay_cells_relayed

uint64_t stats_n_relay_cells_relayed

extern

Stats: how many relay cells have originated at this hop, or have been relayed onward (not recognized at this hop)?

Definition at line 137 of file relay.c.

Referenced by circuit_package_relay_cell(), circuit_receive_relay_cell(), and dumpstats().